Method of notching and shearing the ends of tubing in the preparation of tubular assemblies



Oct. 24, 1961 F. KOSTER 3,005,369

METHOD OF uowcamc AND SHEARING was ENDS OF TUBING IN THE PREPARATION OF TUBULAR ASSEMBLIES Filed Nov. 25. 1957 2 Sheets-Sheet 1 2.6 L L5 1 y 1 60 39 63 4 Fran 1 5 05 522" lmmf W o l ii'arzzeg Oct. 24, 1961 F 'KOSTER ,0 5,369

METHOD OF NOTCHING AND SHEARING THE ENDS 0F TUBING IN THE PREPARATION OF TUBULAR ASSEMBLIES Filed Nov. 25, 1957 2 Sheets-Sheet 2 l W Whul 52 l 421 1 l I i 23 I [F 24 M I z 447 I; 6623 56 56' 51 22 f1 61. 1 ii 61 i 5 3 i 39 59 5 5 1 a1 I 5 6 I 5 29 5 5 57 1 .1 35 5 19 E 34 1 E 1 l "'H 27 MHII 5 g 30 W1 g 3 Ml 39 T g, ;40a 2 -9. 3

Izzv'ezz for (/Z arzzey METHOD OF NOTCG AND SHEARING THE ENDS F TUBING IN PREPARATION OF TUBULAR ASSEIVELES Frank Koster, Stone Park, 111., assignor to Vogel Tool &

Die Corporation, a corporation of Illinois Filed Nov. 25, 1957, Ser. No. 698,491 1 Claim. (Cl. 83--40) Koster Patent 2,704,124 patented March 15, 1955 shows an apparatus particularly adapted for notching the opposed end sections of a tube to permit the tube to be readily assembled to the outer peripheral wall of a second tube. The latter apparatus is also particularly adapted for the preparation of tubing when making 90 degree or T-joints. Neither of the units above mentioned lend themselves particularly to the preparation of a tube end for a tubular assembly when the tubes are positioned with their axes in acute angle relation. Methods have previously been tried in the preparation of tube ends which purported to prepare the tube in such a manner that angular joints could be easily effected. However, none of the methods and apparatus previously employed have accomplished this result to a satisfactory degree.

In the preparation of tube ends for making acute angular assemblies, it is desirable, in the preparation, to shear the tube end completely to the outer wall so that a close or snug fit is obtained. A snug or close fit in the manufacture of tubular assemblies is particularly important, since such assemblies are secured together by means of brazing, the said operation requiring a very close or snug connection in order to secure proper bonding of the metal surfaces to another. In order to secure such close fit between the edges of the prepared tube and the peripheral wall of the connected tube, it is necessary to prepare the said edges so that they are in complete conformance with the contour of the tube, and the method by which this is done, and the apparatus used, is considered critical. Thus, it is applicants prime object of this invention to provide an improved method and apparatus particularly suited for the preparation of tube ends wherein the tube end is connected to the peripheral wall of another tube in acute angle relation.

Still another object of the invention is to provide an improved method for preparing the ends of a tube, the said method including a shearing operation wherein the end of the tube is sheared in such a manner that a very close and snug fit is obtained when attaching the said tube end to another tube at an acute angle.

A still further object is the provision of a two stage die and punch assembly particularly suited for the notching and preparing of the end of a tube for connection of the said tube to another tube in tubular assembly.

A still further object is the provision of an approved method consisting of a novel series of steps designed to prepare a tube end having very snug connection when assembled in relation to another tube.

These and further objects will become more readily apaprent from a reading of the specification when examined in connection with the accompanying sheet of drawing.

In the drawing:

FIGURE 1 is a side elevational view of a tubular Patented Oct. 24, 1961 ice assembly showing a prepared tube end in connected relation with respect to another tube;

FIGURE 2 is a cross-sectional view taken along the line 22 of FIGURE 1; I

FIGURE 3 is a perspective view of a tube end showing t2: first stage in the operation of preparing the end of a tu e;

FIGURE 3-A is a cross-sectional view taken substantially along the line 3A-3A of FIGURE 3;

FIGURE 4 is a perspective view of a tube end having a notching and shearing operation thereon performed to completion;

FIGURE 5 is a fragmentary view taken substantially along the line 5-5 of FIGURE 4;

FIGURE 6 is a plan view of an apparatus for preparing the end of a tube;

FIGURE 7 is a front elevational view of the apparatus shown in FIGURE 6;

FIGURE 8 is a cross-sectional view taken substantially along the line 88 of FIGURE 7; and

FIGURE 9 is a cross-sectional view taken substantially along the line 9--9 of FIGURE 7.

Referring now particularly to FIGURE 1 a tubular assembly 10 is indicated. The tubular assembly 10 is of the acute angular type in that a tube 11 is connected to a tube 12 with the axes of said tubes in angular relation. The assembly shows the tube 12 to have a tube end 13 which has its ends prepared in such a manner that it provides a close and snug fit against the outer peripheral wall of the tube 11. As indicated in FIG- URE 3, the tube end 13 is first prepared with a slot generally designated at 14, the said slot having vertical sides 15 with respect to a transversely extending plane designated generally by the line AA shown in FIG- URE 3. The vertical sides 15 are joined, at the inner end of the tube end 13, by means of a wall 16, the said wall being shaped in the shape of an involute curve. In FIGURE 4, after a second operation on the tube end 13, the sides are no longer vertical but are shaped in outwardly diverging relation, as best shown in FIG- URE 5. Further the tube end 13 in FIGURE 4 shows a relatively shallow slot 17 which has been provided in opposed relation with respect to the slot 14.

Referring now particularly to FIGURES 6, 7, 8 and 9, an apparatus for shaping the ends of tubing is generally designated by the reference character20. The apparatus 20 comprises a base plate 21 on which a housing 22 is mounted. The housing 22 consists primarily of aback plate 23 suitably connected by side plates 24. A die assembly generally designated at 24a comprises a pair of laterally spaced die blocks 25 and 26. The die blocks 25 on opposite sides are provided with ears 27 and the die block 26 is provided with opposed cars 28. Outer clamps 29 and an inner clamp 30 suitably-secure the die blocks 25 and 26 to the base plate 21.- The clamps 29 and 30 are suitably screwed to thebase by means of screws 31. Each of thedie blocks 25 and-26 haveat their forward ends, a stop block 32 which is rigidly secured to the base plate 21, the said blocks eachincluding an adjusting screw-33 adapted to rigidly position the .blocks 25 and 26 with respect to movement in a direction away from the housing 22. As best shown in FIGURES 6, 7 and 8, the die block 25 is provided with a horizontal recess 34 which is adapted to receive in nesting relation a tube end. The horizontal recess 34 extends the width of the block 25 and the block 25 is also provided with a vertical arcuate slot 35 which at the juncture of the. recess and slots 34 and 35 respectively formsa cutting edge. The vertical slot is so shaped as to provide a pair 3.8. the

' holder 40a best shown in FIGURES 6, 7 and s.

. .a 1..rccessextending in, an .acute angle with respect to a v upper and meeting with the recess 38 to also form a cutting edge. A punch holder assembly is generally designated at 49. The punch holder assembly includes a punch The .{Pflnchholder'40a has connected thereto a screw 41 which extends through a recess 42 in the back member 23, the

said screw 41 acting as a stop to limit the upward movement of the punch holder 40a- A spring 43 normally urges the punch holder'40a upwardly. The punch holder ,40a 'is provided 'With a boreW44 which is adapted to 2 containin mating relation a shank 45 connected by means of a dowel rod 46 to the punch holder 40a. The shank I45iis' provided with an integral punch 47 having parallel said screw also projecting through a slot 53 formed in the back-up member 23. A spring 54 normally urges the punch'holder 51 in an upward direction. The punchholdor 51 is provided with a recess 55 containing a punch 56. The punch 56 is suitably held in position by means of screws 57 positioned in bores 58 provided in the punch holder 51. The'punch 56 is provided with an outer arcuate'surface 59 which conforms generally to the outer peripheral contour of the tube 11. The punch 56 is provided 'at its lower end with a cutting portion dtl which is v, adapted to suitably associate with the cutting edge of the die' block 26. The punch holders 40a and 51 are suitably f maintained in'position on the housing 22 by means of outer securing plates 61 and inner securing plates 62, the

inner securing plates 62 being suitably connected to a separator wall 63 securely connected to the back-up memb f 2. V

The die'jblocks" and'the punch holder have been dislclosed ,as individual orsepa'rate units but it must be under'stoodthatl the die'blocks may be made in one piece "an'd'the' punch holders also may be made in one piece.

In them'anne'r' shown, however, it is more simple to :sharpen'the' dies: and punches when desired. The apparams 2 0, may be placed'on thebolster plate (not shown) of asuitable pimch'pressand when the ram o'f the press descends" downon' topofthe punch holders'40a and 51, the said punch holders move downwardly so that the punches 47 and 56' engage the die blocks 25 and 26 in shearing relation. Inoperation, as shown in FIGURE 7 8, t he tu b e 12,is placed in position in the recess 34 with the end Cu e tube over the punch 47. The punch holde'r48 isflforced ownw'ardly'fand the punch which conorms to thearcuatefslot35 mo'ves downwardly and the r ialis sheared'fromkhafihside out,"the' slug being f di charged 'throngh the not 35 and opening 50. fAsshown n FIGURES. 3' and 3a thelslotis shaped in'elongated form, the'sides15 hein'g substantially perpendicular to a planeAlthroughjthetube end; The wall 16 'is of involute 'shape conforming to the shape of the slot 35 and the punch 47.." As shown in FIGURES 3 and 3a'the initial slot formed is substantially wide, the intention being to form' as wid'e a' slot as possible. In other words the 1 inch 4] isgdesigned tp takeout as much material as when putting" from the inside out, so thatmost ial wallf extending horizontally is removed portions remaining, on laterally spaced sides, 1 laterally spaced portions, the substantial ighj aregjafter the first shearing force, in ent with vertical tangent. planes jextendin g to the inner 'diamete'r' surfaces of the tube, Thus it is these portions whicharefirst engaged in shearing relation by the punch cutting surface 60 which moves into engagement with the vertical portions in a vertical direction. By removing most of the horizontal portions of the tube by the first shearing force and during the shearing of the Wide slot, tearing and deformation is eliminated by the action of the second punch during the second shearing operation. Thus the sideslS are disposed substantially close to and parallel to the laterally spaced vertical planes tangent to the laterally spaced inner diameter surfaces of the tube. This provides that the greater parts, after the first shearing operation, of the laterally spaced portions are in vertical alignment or are parallel to the tangent planes. Thus these portions by virtue .of their vertical position relative to the vertical movement of the punch 59, have sufiicient inherent resistance so that they will shear cleanly without tearing, distortion, or deformation. It has been found, that, as shown in FIGURE 3a, the initial slot should be at least greater than the radius of the tube, or stated in another manner at least greater than one-half of the diameter. 7

The tube 12 is then placed into the recess 38 in the manner shown in FIGURE 9 and the punch holder 51 is then forced downwardly whereupon the cutting edge 60 and punch 56 is moved downwardly through the slot 14, the cutting edge 69 first engaging the sides 15 of the tube end at opposite spaced points as indicated by the line B-B in FIGURE 4. As the punch 56 travels down- Wardly the shearing edge of the slot 39 and the cutting portion 60 are effective to progressively shear the sides 15 in an inward direction. The sheared material actually is forced inwardly, and the slot 15 now becomes 7 larger and the sides 15 now assume the divergingrela- 7 ing action so that sides 15 are cleanly sheared. Con- 1 the small radius 17 when in the assembled position of the tubes snugly fits with respect to the contour of the t e. 11-

Likewise the involute shaped wall 16 in the position indicated snugly fits the contour of the said tube 11. By virtue of the fact that the sides 15 in the finished condition of the tube are in the tapered or diverging relation the 'tube 12. snugly fits against the tube 11 and a therefore, in assembly a perfect fit will be obtained. Also as indicated in FIGURE 9 the tube 12 is placed at the same angle, with respect to the arcuate surface .49 as it would be when it is placed against the tube in assembled condition as shown in FIGURE 1. The arcuate surface 59 also is of thesamecontour as the tube 11. Also by positioning the tube 12 in the manner indicated, as the punch 56 performs its shearing action, it has. a tendency to draw the tube downwardly to prevent the same from backing off from the die block 26.

Thus it can be seen that the objects of the invention have been fully achieved and an improved method and apparatus for preparing the ends of a tube have been described.

It must be understood that changes and modifications may bemade. without departingfrom the spirit. of the invention as disclosed or the scope thereof as defined in the appended claim.

What is claimed is.

A method of shearing one end of a cylindrical memher to shape the end thereof to fit against theiside Wall of a similar cylindrical member in a snug manner through- 8 out the entire periphery of the contacting surface of the said two members, said method including selecting a female die having a grooved surface complementary to the cylindrical surface of the tube to be sheared and having a recess in the bottom of said groove of a circumferential extent less than one-half of but more than one-quarter of the circumference of said tube, the inner walls of said recess being joined by a curved wall, selecting a male die having a horizontal face and two vertical faces normal thereto and spaced apart a distance suflicient to form a snug sliding fit with the recess of said female die; and having one end thereof shaped complementary to the curved end of said recess in said female die, forming the complementary faces of the male and female dies with cutting edges, disposing said dies with their cutting edges in a nesting cutting relation, mounting a tube to be sheared in the groove of said female die with said end of said tube overlying said recess, confining the portion of said tube overhanging said recess to prevent the tube edge portions from flairing during punching, mounting said male die interiorly of said tube and above said recess and punching the tube from Within so as to form a slot having axially extending sides converging at a sharp acute angle with the remaining periphery, supporting said tube in a second similarly grooved female and recessed die with the first formed slot diametrically opposite the bottom of the groove, selecting a second male die shaped complementarily to said second female die, disposing said dies with the axes thereof at an angle to each other, passing said male die through the slotted portion of said tube at an angle to the axis thereof from a point adjacent the rear edge of said slot toward the diametrically opposed portion of said tube and shearing said tube to remove an end portion of the tube so that the cut Walls of the tube have the edges resulting from the cut converging at a. sharp angle with the remaining periphery of said tube.

References Cited in the file of this patent UNITED STATES PATENTS Re. 22,114 Borzym June 16, 1942 1,389,881 Kraut Sept. 6, 1921 1,428,355 Bradley Sept. 5, 1922 1,582,052 Kloges Apr. 27, 1926 2,064,539 Hart r Dec. 15, 1936 2,335,720 Yeomans Nov. 30, 1943 2,613,740 Drain Oct. 14, 1952 2,619,172 Flittner Nov. 25, 1952 2,648,380 Socke r Aug. 11, 1953 2,648,381 Engel Aug. 11, 1953 2,704,124 Koster Mar. 15, 1955 2,765,848 Bakula Oct. 9, 1956 2,783,840 Snorek Mar. 5, 1957 FOREIGN PATENTS 22,336 Great Britain Oct. 21, 1908 545,782 Italy July 5, 1956 906,531 Germany Mar. 15, 1954 

